This invention relates generally to an antifriction roller bearing cage structure and more particularly to a cage structure having a crossbar which enhances roller retention and a method for making the enhanced retention retainer.
A typical retainer for needle bearings uses a crossbar having an approximate trapezoidal shape. The sides of the crossbar are angled away from the rollers and toward the center of the bearing housing. Such a configuration results in minimal retention of the roller. As the roller moves toward the center of the bearing, the distance between adjacent retainer crossbars becomes larger because of the angle of the crossbar sides away from the rollers.
The common method for manufacturing needle bearing retainers is to use a slot pierce operation on a blank strip of metal. A plurality of slots are pierced in the strip. Typically the piercing is done from the outer radial side of the strip. After the slots have been pierced in the strip, the strip is cut off to the desired length, the cutoff strip is wrapped into the circular shape of the retainer and the ends are welded together. This results in any burr from the piercing operation being on the inner radial surface of the retainer where the burrs can score and damage the shaft. Customary burr removal techniques involve chemical milling or tumble processing, either of which consume time in the manufacturing cycle and require control of effluent discharges.
The foregoing illustrates limitations known to exist in present needle bearing retainers. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.